Display Device Having Touch Sensors and Method of Manufacturing the Same

ABSTRACT

Disclosed is a display device having touch sensors which may reduce parasitic capacitance and a method of manufacturing the same. The display device includes a plurality of touch sensing lines respectively arranged so as to traverse a plurality of common electrode blocks forming an electric field with pixel electrodes, a lower planarization layer having openings in regions overlapping drain electrodes of thin film transistors, an upper planarization layer arranged between one of the pixel electrodes and the common electrode blocks, and the touch sensing lines so as to cover a side surface of the lower planarization layer, and an upper protective film arranged between the pixel electrodes and the common electrode blocks, and, thus, parasitic capacitance generated between the touch sensing lines and the common electrode blocks may be reduced without reduction in liquid crystal capacitance and storage capacitance.

CROSS-REFERENCE TO RELATED APPLICATIONS

This application claims the benefit of the Republic of Korea PatentApplication No. 10-2017-0171289, filed on Dec. 13, 2017, which is herebyincorporated by reference in its entirety.

BACKGROUND Technical Field

The present disclosure relates to a display device and a method ofmanufacturing the same, and more particularly, to a display devicehaving touch sensors which may reduce parasitic capacitance and a methodof manufacturing the same.

Discussion of the Related Art

A touch panel is one kind of input device which is provided in a displaydevice, such as a liquid crystal display device, an organic lightemitting display device or an electrophoretic display device, so that auser may input information by directly contacting a screen using afinger or a stylus pen.

Recently, in order to satisfy slimness of portable terminals, such assmartphones, tablet PCs, etc., demand for a display device, in whichtouch sensors constituting a touch panel are installed within a displaypanel of the display device, is increasing.

However, in such a display device having built-in touch sensors, aplurality of electrodes or signal lines of a display panel are arrangedaround the touch sensors. Unnecessary parasitic capacitances are formeddue to these electrodes or signal lines of the display panel. Theparasitic capacitances increase a touch driving load and lower accuracyin touch sensing, or, in severe cases, may cause impossibility ofsensing touch.

SUMMARY

Accordingly, the present disclosure is directed to a display devicehaving touch sensors and a method of manufacturing the same thatsubstantially obviates one or more problems due to limitations anddisadvantages of the related art.

An object of the present disclosure is to provide a display devicehaving touch sensors which may reduce parasitic capacitance and a methodof manufacturing the same.

Additional advantages, objects, and features of the disclosure will beset forth in part in the description which follows and in part willbecome apparent to those having ordinary skill in the art uponexamination of the following or may be learned from practice of thedisclosure. The objectives and other advantages of the disclosure may berealized and attained by the structure particularly pointed out in thewritten description and claims hereof as well as the appended drawings.

To achieve these objects and other advantages and in accordance with thepurpose of the disclosure, as embodied and broadly described herein, adisplay device having touch sensors includes a plurality of touchsensing lines respectively arranged so as to traverse a plurality ofcommon electrode blocks forming an electric field with pixel electrodes,a lower planarization layer having openings in regions overlapping drainelectrodes of thin film transistors, and an upper planarization layerarranged between one of the pixel electrodes and the common electrodeblocks, and the touch sensing lines so as to cover a side surface of thelower planarization layer.

Some embodiments relate to a display device having touch sensorscomprising: a plurality of thin film transistors arranged on asubstrate; a plurality of pixel electrodes, each of the plurality ofpixel electrodes connected to a corresponding one of the plurality ofthin film transistors; a plurality of common electrode blocks configuredto form an electric field with the plurality of pixel electrodes, theplurality of common electrodes arranged on the substrate; a plurality oftouch sensing lines, each of the plurality of touch sensing linesconnected to a corresponding one of the plurality of common electrodeblocks; a lower protective film arranged between the plurality of thinfilm transistors and the plurality of touch sensing lines, the lowerprotective film having a plurality of openings overlapping drainelectrodes of the plurality of thin film transistors; a lowerplanarization layer arranged on the lower protective film, the lowerplanarization layer having a plurality of openings overlapping theplurality of openings of the lower protective film; an upperplanarization layer arranged between one of the plurality of pixelelectrodes and the plurality of common electrode blocks, and theplurality of touch sensing lines, wherein side surfaces of the upperplanarization layer cover side surfaces of the lower planarization layerexposed by the plurality of openings of the lower planarization layer,and wherein the side surfaces of the upper planarization layer, theplurality of openings in the lower planarization layer, and theplurality of openings in the lower protective film form pixel contactholes that expose the drain electrodes of the plurality of thin filmtransistors; and an upper protective film arranged between the pixelelectrodes and the common electrode blocks, wherein the plurality ofpixel electrodes contact side surfaces of the upper planarization layerand the lower protective film exposed by the pixel contact holes.

Some embodiments relate to a method of manufacturing a display devicehaving touch sensors, comprising: forming a plurality of thin filmtransistors on a substrate; forming a lower protective film so as tocover the plurality of thin film transistors, the lower protective filmhaving a plurality of openings overlapping drain electrodes of theplurality of thin film transistors; forming a lower planarization layeron the lower protective film, the lower planarization layer having aplurality of openings overlapping the openings of the lower protectivefilm; forming a plurality of touch sensing lines on the lowerplanarization layer; forming an upper planarization layer on theplurality of touch sensing lines and the lower planarization layer,wherein side surfaces of the upper planarization layer cover sidesurfaces of the lower planarization layer exposed by the plurality ofopenings of the lower planarization layer, and wherein the side surfacesof the upper planarization, the plurality of openings in the lowerplanarization layer, and the plurality of openings in the lowerprotective film form pixel contact holes that expose the drainelectrodes of the plurality of thin film transistors; forming aplurality of pixel electrodes, each of the plurality of pixel electrodesconnected to a corresponding one of the plurality of thin filmtransistors through side surfaces of the pixel contact holes; forming anupper protective film on the upper planarization layer and the pluralityof pixel electrodes; and forming a plurality of common electrode blocksconfigured to form an electric field with the plurality of pixelelectrodes, each of the plurality of common electrode blocks arranged onthe upper protective film to be connected to a corresponding one of theplurality of touch sensing lines.

Some embodiments relate to a display device having touch sensorscomprising: a substrate; a thin film transistor (TFT) arranged on thesubstrate, wherein the TFT includes an electrode; a first protectivefilm on the TFT, the first protective film including a hole that exposesa portion of an electrode of the TFT; a first planarization layer overthe first protective film and the TFT, the first planarization layerincluding a hole overlapping the portion of the electrode exposedthrough the hole in the first protective film; a touch sensing line(TSL) on the lower planarization layer; a second planarization layerover the TSL and the first planarization layer, the second planarizationlayer covering a side surface of the first planarization layer exposedby the hole in the first planarization layer such that a hole is formedin the second planarization layer; a pixel electrode on the secondplanarization layer, the pixel electrode electrically connected to theelectrode of the TFT through the hole in the second planarization layer,the hole in the first planarization layer, and the hole in the firstprotective film; and a common electrode block over the pixel electrodethe common electrode block electrically connected to the TSL.

It is to be understood that both the foregoing general description andthe following detailed description of the present disclosure areexemplary and explanatory and are intended to provide furtherexplanation of the invention as claimed.

BRIEF DESCRIPTION OF THE DRAWINGS

The accompanying drawings, which are included to provide a furtherunderstanding of the disclosure and are incorporated in and constitute apart of this application, illustrate embodiment(s) of the disclosure andtogether with the description serve to explain the principle of thedisclosure. In the drawings:

FIG. 1 is a block diagram illustrating a display device having touchsensors in accordance with an embodiment;

FIG. 2 is a plane view illustrating a display panel having the touchsensors shown in FIG. 1 in more detail, according to an embodiment;

FIG. 3 is an enlarged plan view of a portion “A” of FIG. 2, according toan embodiment;

FIG. 4 is a cross-sectional view of the display panel, taken along lines“I-I′” and “II-II′” of FIG. 3; and

FIGS. 5A to 5G are cross-sectional views illustrating a method ofmanufacturing the display device shown in FIG. 4.

DETAILED DESCRIPTION

Reference will now be made in detail to the preferred embodiments of thepresent disclosure, examples of which are illustrated in theaccompanying drawings.

FIG. 1 is a block diagram illustrating a display device having touchsensors in accordance with one embodiment of the present disclosure.

The display device shown in FIG. 1 includes a data driver 204, a gatedriver 202, a touch driver 206, and a display panel 200.

The data driver 204 converts data from a timing controller (not shown)into analog data voltage and supplies the analog data voltage to datalines DL in response to a data control signal from the timingcontroller.

The gate driver 202 sequentially drives gate lines GL of the displaypanel 200 in response to a gate control signal from the timingcontroller. The gate driver 202 supplies a scan pulse of a gate-onvoltage to each gate line GL during a scan period of the correspondinggate line GL, and supplies a gate-off voltage to the corresponding gateline GL during remaining periods when other gate lines GL are driven.The gate driver 202 is formed together with thin films transistors ofrespective pixels during a process of manufacturing the thin filmtransistors and is located at a non-display area formed at one side orboth sides of a substrate of the display panel 200.

The touch driver 206 is connected to touch sensing lines TSL of thedisplay panel 200 and thus receives a user touch signal from the touchsensing lines TSL. The touch driver 206 detects whether or not usertouch occurs and a touch position by sensing change in capacitance dueto the user touch.

In the display panel 200, a plurality of pixels are arranged in a matrixand thus displays an image. If a liquid crystal panel is used as thedisplay panel 200, the display panel 200 may include a color filtersubstrate on which a color filter array is formed, a thin filmtransistor substrate on which a thin film transistor array is formed,and a liquid crystal layer provided between the color filter substrateand the thin film transistor substrate.

The display panel 200 includes an active area AA and a bezel area BAarranged at at least one side of the active area AA, as exemplarilyshown in FIG. 2.

A plurality of pads connected to the signal lines GL, DL and TSL of theactive are AA are arranged in the bezel area BA. That is, gate pads (notshown) connected to the gate lines GL, data pads (not shown) connectedto the data lines DL and common pads (not shown) connected to the touchsensing lines TSL are arranged in the bezel area BA. Further, at leastone of the gate driver 202, the data driver 204, or the touch driver 206may be arranged in the bezel area BA.

A plurality of common electrode blocks 132 and a plurality of touchsensing lines TSL respectively connecting the common electrode blocks132 to the touch driver 206 are arranged in the active area AA. Here,each touch sensing line TSL is arranged so as to extend in a vertical orhorizontal direction and thus to traverse the common electrode blocks132. For example, the touch sensing lines TSL may be arranged so as toextend in a direction parallel to the data lines DL and thus to traversethe common electrode blocks 132, which are arranged in the direction ofthe data lines DL.

In the example of FIG. 2, a plurality of the common electrode blocks 132are arranged in a first direction parallel to the gate lines GL and in asecond direction parallel to the data lines DL. The common electrodeblocks 132 may also be arranged so as to be spaced apart from eachother.

The common electrode blocks 132 are formed by dividing a commonelectrode of the display device into a plurality of pieces. The commonelectrode blocks 132 can operate as common electrodes during an imagedisplay period, and can operate as touch electrodes during a touchsensing period. That is, during the image display period, the commonelectrode blocks 132 receive a common voltage supplied through the touchsensing lines TSL. Further, during the touch sensing period (e.g., animage non-display period) the common electrode blocks 132 supply sensedtouch sensing voltages to the touch driver 206 through the touch sensinglines TSL.

Each of the common electrode blocks 132 can have a size corresponding toat least two pixel areas in consideration of a user touch area.Therefore, one common electrode block 132 may be arranged so as tooverlap a plurality of pixel electrodes 122, as exemplarily shown inFIG. 3.

The pixel electrode 122 is connected to a thin film transistor 100 ineach pixel area, prepared by intersection of the gate line GL and thedata line DL, as exemplarily shown in FIG. 4.

The thin film transistor 100 charges the pixel electrode 122 with a datasignal of the data line DL in response to a scan signal of the gate lineGL (not shown in FIG. 4) and maintains the charged state of the pixelelectrode 122. For this purpose, the thin film transistor 100 includes agate electrode 106 connected to the gate line GL, a source electrode 108connected to the data line DL, a drain electrode 110 connected to thepixel electrode 122, and a semiconductor layer formed on a gateinsulating film 112 so as to form a channel between the source electrode108 and the drain electrode 110. Here, the semiconductor layer includesan active layer 102 and an ohmic contact layer 104. The active layer 102is formed on the gate insulating film 112 so as to overlap the gateelectrode 106, thus forming the channel between the source and drainelectrodes 108 and 110. The ohmic contact layer 104 is formed on theactive layer 102 except for the channel so as to form ohmic contactbetween each of the source and drain electrodes 108 and 110 and theactive layer 102. The active layer 102 and the ohmic contact layer 104are formed to overlap the data line DL as well as the source and drainelectrodes 108 and 110.

A lower protective film 118, a lower planarization layer 116, aninterlayer protective film 124, an upper planarization layer 126, and anupper protective film 128 are sequentially stacked on the thin filmtransistor 100.

Each of the lower protective film 118, the interlayer protective film124 and the upper protective film 128 is formed to have a monolayer ormultilayer structure using an inorganic insulating material, such asSiN_(x), SiON, or SiO₂. Particularly, if the active layer 102 is formedof an oxide semiconductor, the lower protective film 118 contacting theactive layer 102 may be formed of silicon oxide (SiO_(x)) having a lowerhydrogen content than silicon nitride (SiN_(x)) grown as a film usinghydrogen gas. Therefore, diffusion of hydrogen into the active layer 102during formation of the lower protective film 118 may be prevented andthus a change in a threshold voltage of the thin film transistor 100 maybe prevented. Further, the interlayer protective film 124 can be formedof silicon nitride (SiN_(x)) and may thus prevent oxidation of the touchsensing lines TSL.

Each of the lower planarization layer 116 and the upper planarizationlayer 126 can be formed of a photosensitive organic insulating materialso as not to require an etching process. For example, the lowerplanarization layer 116 and the upper planarization layer 126 is formedof a photoacryl, parylene, or siloxane-based organic insulatingmaterials. Here, the lower planarization layer 116 has an opening 116Ain a region overlapping the drain electrode 110 of the thin filmtransistor 100. The upper planarization layer 126 and the interlayerprotective film 124 are arranged to cover the side surface of the lowerplanarization layer 116 exposed through the opening 116A. Thereby, apixel contact hole 120 formed through the upper planarization layer 126,the interlayer protective film 124 and the lower protective film 118 isarranged within the opening 116A so as to have a smaller line width thanthat of the opening 116A. Since the interlayer protective film 124 andthe lower protective film 118 are self-aligned under the upperplanarization layer 126 between the upper planarization layer 126 andthe drain electrode 110 around the pixel contact hole 120, only theinterlayer protective film 124 and the lower protective film 118 arearranged between the upper planarization layer 126 and the drainelectrode 110 around the pixel contact hole 120.

As such, in the present disclosure, the lower protective film 118 formedof an inorganic insulating material is arranged between the thin filmtransistor 100 and the lower planarization layer 116 formed of anorganic insulating material, and the interlayer protective film 124formed of an inorganic insulating material is arranged between the touchsensing line TSL and the upper planarization layer 126 formed of anorganic insulating material. The lower protective film 118 and theinterlayer protective film 124 formed of inorganic insulating materialscan have excellent adhesive strength with the thin film transistor 100and the touch sensing line TSL, as compared to the lower and upperplanarization layers 116 and 126 formed of organic insulating materials.Therefore, separation of the lower protective film 118 and theinterlayer protective film 124 from the upper surfaces of the thin filmtransistor 100 and the touch sensing line TSL may be prevented and,thus, oxidation of the thin film transistor 100 and the touch sensingline TSL may be prevented.

The pixel electrode 122 is conductively connected to the drain electrode110 exposed through the pixel contact hole 120 formed through the lowerprotective film 118, the interlayer protective film 124 and the upperplanarization layer 126. The pixel electrode 122 directly contacts theside surface of each of the lower protective film 118, the interlayerprotective film 124 and the upper planarization layer 126, exposedthrough the pixel contact hole 120.

Here, the side surface of the upper planarization layer 126 formed of anorganic insulating material and the side surfaces of the lowerprotective film 118 and the interlayer protective film 128 formed ofinorganic insulating materials are exposed through the same pixelcontact hole 120. Therefore, the present disclosure may minimize thenumber of necessary pixel contact holes 120 and, thus, reduce an areaoccupied by the pixel contact holes 120 and improve an aperture ratio.

The common electrode block 132 is formed on the upper protective film128 of each pixel area so as to have a plurality of slits 130. Thecommon electrode block 132 overlaps the pixel electrode 122 with theupper protective film 128 disposed between each pixel area and thusforms a fringe field. Thereby, during the image display period, a commonvoltage is supplied to the common electrode block 132, the commonelectrode block 132 to which the common voltage is supplied, forms thefringe field with the pixel electrode 122 to which a pixel voltagesignal is supplied, and, thus, liquid crystal molecules arranged betweenthe thin film transistor substrate and the color filter substrate arerotated by dielectric anisotropy. Further, light transmissivity of thepixel area is varied according to a degree of rotation of the liquidcrystal molecules and, thus, gradation is implemented.

Further, the common electrode blocks 132 serve as touch electrodes whichsense a user's touch position during the touch sensing period, e.g., theimage non-display period.

For this purpose, each common electrode block 132 is connected to one ofthe touch sensing lines TSL traversing the common electrode block 132.For example, the common electrode block 132 shown in FIG. 3 is connectedto a first touch sensing line TSL1 out of first to third touch sensinglines TSL1, TSL2, and TSL3 (not shown in FIG. 3). In more detail, thetouch sensing line TSL is arranged on the lower planarization layer 116,exposed through a first touch contact hole 166 formed through theinterlayer protective film 124 and the upper planarization layer 126 anda second touch contact hole 168 formed through the upper protective film128, and connected to the common connection electrode 162 arranged onthe upper protective film 128.

Each common electrode block 132 is not connected to the remaining touchsensing lines TSL except for one of the touch sensing lines TSLtraversing the common electrode block 132. For example, the commonelectrode block 132 shown in FIG. 3 is not connected to the second andthird touch sensing lines TSL2 and TSL3 except for the first touchsensing line TSL1 out of the first to third touch sensing lines TSL1,TSL2 and TSL3. In more detail, out of the touch sensing lines TSLtraversing each common electrode block 132, the remaining touch sensinglines TSL which are not connected to the common electrode block 132overlap the common electrode block 132 with the interlayer protectivefilm 124 formed of an inorganic insulating material, the upperplanarization layer 126 formed of an organic insulating material, andthe upper protective film 128 formed of an inorganic insulatingmaterial, disposed between. Therefore, a distance between the touchsensing lines TSL and the common electrode blocks 132 is increased bythe thickness of the upper planarization layer 126 formed of an organicinsulating material and, thus, parasitic capacitance Cc generatedbetween the touch sensing lines TSL and the common electrode blocks 132may be reduced. A touch driving load may be reduced as much as such areduction in the parasitic capacitance Cc and thus accuracy in touchsensing may be improved.

As such, in the present disclosure, the common electrode block 132 andthe pixel electrodes 122 are spaced apart from each other with the upperprotective film 128, formed of an inorganic insulating material,disposed between, and the touch sensing lines TSL and the commonelectrode block 132 are spaced apart from each other with the interlayerprotective film 124 and the upper protective film 128, formed ofinorganic insulating materials, and the upper planarization layer 126,formed of an organic insulating material, disposed between. Therefore,in the present disclosure, parasitic capacitance generated between thetouch sensing lines TSL and the common electrode blocks 132 may bereduced without reduction in liquid crystal capacitance and storagecapacitance generated between the common electrode blocks 132 and thepixel electrodes 122.

FIGS. 5A to 5G are cross-sectional views illustrating a method ofmanufacturing the display device shown in FIG. 4, according to anembodiment.

With reference to FIG. 5A, the data lines DL and the thin filmtransistors 100 are formed on a substrate 101 through at least two maskprocesses.

In more detail, a gate metal layer is deposited on the entire uppersurface of the substrate 101 and then patterned, thus forming the gateelectrodes 106. Thereafter, the gate insulating film 112 is formed bycoating the entire surface of the substrate 101 provided with the gateelectrodes 106 formed thereon with an inorganic insulating material. Asemiconductor material and a data metal layer are sequentially stackedon the gate insulating film 112 and then patterned, thus forming theactive layer 102, the ohmic contact layer 104, the source and drainelectrodes 108 and 110 and the data lines DL.

With reference to FIG. 5B, the lower protective film 118 and the lowerplanarization layer 116 are sequentially formed on the substrate 101provided with the data lines DL and the thin film transistors 100 formedthereon.

In more detail, the lower protective film 118 is formed by stacking aninorganic insulating material on the entire upper surface of thesubstrate 101 provided with the data lines DL and the thin filmtransistors 100 formed thereon. Here, the lower protective film 118 usesan inorganic insulating material, such as SiN_(x), SiON, or SiO₂.Thereafter, an organic insulating material is coated on the entire uppersurface of the lower protective film 118 and then patterned through aphotolithographic process, thus forming the lower planarization layer116 having the openings 116A. The lower planarization layer 116 uses aphotoacryl, parylene, or siloxane-based organic insulating material. Theopenings 116A overlap the drain electrodes 110 of the thin filmtransistors 100.

With reference to FIG. 5C, the touch sensing lines TSL are formed on thesubstrate 101 provided with the lower planarization layer 116 formedthereon.

An opaque conductive layer is deposited on the entire upper surface ofthe substrate 101 provided with the lower planarization layer 116 formedthereon and is then patterned through a photolithographic process and anetching process. Thereby, the touch sensing lines TSL are formed on thelower planarization layer 116. Here, the touch sensing lines TSL areformed of an opaque conductive layer so as to have a monolayer ormultilayer structure using at least one metal selected from the groupconsisting of Al, Ti, Cu, Mo, Ta and MoTi.

With reference to FIG. 5D, the interlayer protective film 124 and theupper planarization layer 126 are formed on the substrate 101 providedwith the touch sensing lines TSL formed thereon.

In more detail, the interlayer protective film 124 is formed bydepositing an inorganic insulating material on the entire upper surfaceof the substrate 101 provided with the touch sensing lines TSL formedthereon. Here, the interlayer protective film 124 uses an inorganicinsulating material, such as SiN_(x), SiON, or SiO₂. Thereafter, theupper planarization layer 126 is formed by depositing an organicinsulating material on the entire upper surface of the interlayerprotective film 124. The upper planarization layer 126 uses aphotoacryl, parylene, or siloxane-based organic insulating material. Theupper planarization layer 126 is patterned through a photolithographicprocess, thus forming the pixel contact holes 120 and the first touchcontact holes 166. Thereafter, the interlayer protective film 124 andthe lower protective film 118 are etched through an etching processusing the upper planarization layer 126 as a mask. Thereby, the pixelcontact holes 120 are formed through the upper planarization layer, theinterlayer protective film 124, and the lower protective film 118 andthus expose the drain electrodes 110. Furthermore, the first touchcontact holes 166 are formed through the upper planarization layer 126and the interlayer protective film 124 and thus expose the touch sensinglines TSL.

With reference to FIG. 5E, the pixel electrodes 122 are formed on thesubstrate 101 provided with the interlayer protective film 124 and theupper planarization layer 126 formed thereon.

In more detail, a transparent conductive layer is deposited on theentire upper surface of the substrate 101 provided with the upperplanarization layer 126 formed thereon. Thereafter, the transparentconductive layer is patterned through a photolithographic process and anetching process, thus forming the pixel electrodes 122.

With reference to FIG. 5F, the upper protective film 128 having thesecond touch contact holes 168 is formed on the substrate 101 providedwith the pixel electrodes 122 formed thereon.

In more detail, the upper protective film 128 using an inorganicinsulating material, such as SiN_(x), SiON, or SiO₂, is formed on theentire surface of the substrate 101 provided with the pixel electrodes122 formed thereon. Thereafter, the upper protective film 128 ispatterned through a photolithographic process and an etching process,thus forming the second touch contact holes 168 exposing the touchsensing lines TSL.

With reference to FIG. 5G, the common electrode blocks 132 are formed onthe substrate 101 having the second touch contact holes 168.

In more detail, a transparent conductive film is deposited on the entireupper surface of the substrate 101 having the second touch contact holes168. Thereafter, the transparent conductive layer is patterned through aphotolithographic process and an etching process, thus forming thecommon electrode blocks 132.

Although the present disclosure exemplarily describes a structure inwhich the pixel electrodes 122 are arranged below the common electrodeblocks 132, the common electrode blocks 132 may be arranged below thepixel electrodes 122.

As apparent from the above description, in a display device having touchsensors in accordance with the present disclosure, common electrodeblocks and pixel electrodes are spaced apart from each other with anupper protective film formed of an inorganic insulating material,disposed between, and touch sensing lines and the common electrodeblocks are spaced apart from each other with an interlayer protectivefilm and the upper protective film formed of inorganic insulatingmaterials and an upper planarization layer formed of an organicinsulating material, disposed between. Therefore, in the presentdisclosure, parasitic capacitance generated between the touch sensinglines and the common electrode blocks may be reduced without reductionin liquid crystal capacitance and storage capacitance generated betweenthe common electrode blocks and the pixel electrodes. Further, in thepresent disclosure, the side surface of the upper planarization layerformed of an organic insulating material and the side surfaces of alower protective film and the interlayer protective film formed ofinorganic insulating materials are exposed through the same pixelcontact hole and, thus, the pixel electrode is conductively connected toa drain electrode exposed through one pixel contact hole. Therefore, thedisplay device in accordance with the present disclosure may minimizethe number of necessary pixel contact holes and, thus, reduce an areaoccupied by the pixel contact holes and improve an aperture ratio.Moreover, in the present disclosure, the pixel contact holes formedthrough the lower protective film and the interlayer protective film areformed using the upper planarization layer as a mask and, thus, amanufacturing process of the display device may be simplified andmanufacturing costs of the display device may be reduced.

It will be apparent to those skilled in the art that variousmodifications and variations can be made in the present disclosurewithout departing from the spirit or scope of the disclosure. Thus, itis intended that the present disclosure cover the modifications andvariations of this disclosure provided they come within the scope of theappended claims and their equivalents.

What is claimed is:
 1. A display device having touch sensors comprising:a plurality of thin film transistors arranged on a substrate; aplurality of pixel electrodes, each of the plurality of pixel electrodesconnected to a corresponding one of the plurality of thin filmtransistors; a plurality of common electrode blocks configured to forman electric field with the plurality of pixel electrodes, the pluralityof common electrodes arranged on the substrate; a plurality of touchsensing lines, each of the plurality of touch sensing lines connected toa corresponding one of the plurality of common electrode blocks; a lowerprotective film arranged between the plurality of thin film transistorsand the plurality of touch sensing lines, the lower protective filmhaving a plurality of openings overlapping drain electrodes of theplurality of thin film transistors; a lower planarization layer arrangedon the lower protective film, the lower planarization layer having aplurality of openings overlapping the plurality of openings of the lowerprotective film; an upper planarization layer arranged between one ofthe plurality of pixel electrodes and the plurality of common electrodeblocks, and the plurality of touch sensing lines, wherein side surfacesof the upper planarization layer cover side surfaces of the lowerplanarization layer exposed by the plurality of openings of the lowerplanarization layer, and wherein the side surfaces of the upperplanarization layer, the plurality of openings in the lowerplanarization layer, and the plurality of openings in the lowerprotective film form pixel contact holes that expose the drainelectrodes of the plurality of thin film transistors; and an upperprotective film arranged between the pixel electrodes and the commonelectrode blocks, wherein the plurality of pixel electrodes contactsside surfaces of the upper planarization layer and the lower protectivefilm exposed by the pixel contact holes.
 2. The display device accordingto claim 1, further comprising: an interlayer protective film arrangedbetween the plurality of touch sensing lines and the upper planarizationlayer, the interlayer protective film having a plurality of openingsoverlapping the plurality of openings of the lower protective film,wherein side surfaces of the upper planarization layer, the plurality ofopenings of the interlayer protective film, and the plurality ofopenings of the lower protective film form the pixel contact holes. 3.The display device according to claim 2, wherein each of the upperplanarization layer and the lower planarization layer comprises anorganic insulating material, and each of the lower protective film, theinterlayer protective film, and the upper protective film comprises aninorganic insulating material.
 4. The display device according to claim2, wherein: one of the plurality of touch sensing lines that traverseseach of the plurality of common electrode blocks is exposed through atouch contact hole formed through the interlayer protective film, theupper planarization layer, and the upper protective film and isconnected to a corresponding one of the plurality of common electrodeblocks; and a remainder of the plurality of touch sensing linestraverses the corresponding one of the plurality of common electrodeblocks by overlapping the corresponding common electrode block with theinterlayer protective film, the upper planarization layer, and the upperprotective film disposed between the remainder of the plurality of touchsensing lines and the corresponding common electrode block.
 5. Thedisplay device according to claim 3, wherein: one of the plurality oftouch sensing lines that traverses each of the plurality of commonelectrode blocks is exposed through a touch contact hole formed throughthe interlayer protective film, the upper planarization layer, and theupper protective film and is connected to a corresponding one of theplurality of common electrode blocks; and a remainder of the pluralityof touch sensing lines traverses the corresponding one of the pluralityof common electrode blocks by overlapping the corresponding one of theplurality of common electrode blocks with the interlayer protectivefilm, the upper planarization layer, and the upper protective filmdisposed between the remainder of the plurality of touch sensing linesand the corresponding common electrode block.
 6. The display deviceaccording to claim 1, wherein: the plurality of pixel electrodes isarranged on the upper planarization layer, and the plurality of commonelectrode blocks is arranged on the upper protective film and cover theplurality of pixel electrodes.
 7. A method of manufacturing a displaydevice having touch sensors, comprising: forming a plurality of thinfilm transistors on a substrate; forming a lower protective film thatcovers the plurality of thin film transistors, the lower protective filmhaving a plurality of openings overlapping drain electrodes of theplurality of thin film transistors; forming a lower planarization layeron the lower protective film, the lower planarization layer having aplurality of openings overlapping the openings of the lower protectivefilm; forming a plurality of touch sensing lines on the lowerplanarization layer; forming an upper planarization layer on theplurality of touch sensing lines and the lower planarization layer,wherein side surfaces of the upper planarization layer cover sidesurfaces of the lower planarization layer exposed by the plurality ofopenings of the lower planarization layer, and wherein the side surfacesof the upper planarization, the plurality of openings in the lowerplanarization layer, and the plurality of openings in the lowerprotective film form pixel contact holes that expose the drainelectrodes of the plurality of thin film transistors; forming aplurality of pixel electrodes, each of the plurality of pixel electrodesconnected to a corresponding one of the plurality of thin filmtransistors through side surfaces of the pixel contact holes; forming anupper protective film on the upper planarization layer and the pluralityof pixel electrodes; and forming a plurality of common electrode blocksconfigured to form an electric field with the plurality of pixelelectrodes, each of the plurality of common electrode blocks arranged onthe upper protective film to be connected to a corresponding one of theplurality of touch sensing lines.
 8. The method according to claim 7,further comprising: forming an interlayer protective film arrangedbetween the touch sensing lines and the upper planarization layer, theinterlayer protective film having a plurality of openings overlappingthe openings of the plurality of openings of the lower protective film,wherein side surfaces of the upper planarization layer, the plurality ofopenings of the interlayer protective film, and the plurality ofopenings of the lower protective film form the pixel contact holes. 9.The method according to claim 8, wherein each of the upper planarizationlayer and the lower planarization layer is formed of an organicinsulating material, and each of the lower protective film, theinterlayer protective film, and the upper protective film is formed ofan inorganic insulating material.
 10. The method according to claim 8,further comprising forming a plurality of touch contact holes throughthe interlayer protective film, the upper planarization layer, and theupper protective film to expose the plurality of touch sensing lines,wherein one of the plurality of touch sensing lines that traverses eachof the plurality of common electrode blocks is exposed through one ofthe plurality of touch contact holes and is connected to a correspondingone of the plurality of common electrode blocks, and wherein a remainderof the plurality of touch sensing lines traverses the corresponding oneof the plurality of common electrode blocks by overlapping thecorresponding common electrode block with the interlayer protectivefilm, the upper planarization layer, and the upper protective filmdisposed between the remainder of the touch sensing lines and thecorresponding common electrode block.
 11. The method according to claim9, further comprising: forming a plurality of touch contact holesthrough the interlayer protective film, the upper planarization layer,and the upper protective film to expose the plurality of touch sensinglines, wherein one of the plurality of touch sensing lines thattraverses each of the plurality of common electrode blocks is exposedthrough one of the plurality of touch contact holes and is connected toa corresponding one of the plurality of common electrode blocks, andwherein a remainder of the plurality of touch sensing lines traversesthe corresponding one of the plurality of common electrode blocks byoverlapping the corresponding one of the plurality of common electrodeblocks with the interlayer protective film, the upper planarizationlayer, and the upper protective film disposed between the remainder ofthe touch sensing lines and the corresponding common electrode block.12. The method according to claim 8, wherein the plurality of openingsof the lower protective layer and the plurality of openings of theinterlayer protective film are formed through an etching process,wherein the upper planarization layer acts as a mask.
 13. A displaydevice having touch sensors comprising: a substrate; a thin filmtransistor (TFT) arranged on the substrate, wherein the TFT includes anelectrode; a first protective film on the TFT, the first protective filmincluding a hole that exposes a portion of an electrode of the TFT; afirst planarization layer over the first protective film and the TFT,the first planarization layer including a hole overlapping the portionof the electrode exposed through the hole in the first protective film;a touch sensing line (TSL) on the lower planarization layer; a secondplanarization layer over the TSL and the first planarization layer, thesecond planarization layer covering a side surface of the firstplanarization layer exposed by the hole in the first planarization layersuch that a hole is formed in the second planarization layer; a pixelelectrode on the second planarization layer, the pixel electrodeelectrically connected to the electrode of the TFT through the hole inthe second planarization layer, the hole in the first planarizationlayer, and the hole in the first protective film; and a common electrodeblock over the pixel electrode the common electrode block electricallyconnected to the TSL.
 14. The display device of claim 13, wherein thepixel electrode is in contact with a side surface of the hole in thesecond planarization layer.
 15. The display device of claim 13, furthercomprising: an interlayer protective film between the secondplanarization layer and the TSL arranged on the first planarizationlayer, wherein the interlayer protective film covers the side surface ofthe hole of the first planarization layer; and a second protective filmon the pixel electrode and the second planarization layer.
 16. Thedisplay device of claim 15, wherein the first protective layer, theinterlayer protective film, and the second protective film includeinorganic insulating materials.
 17. The display device of claim 16,wherein the interlayer protective film reduces oxidation of the TSL. 18.The display device of claim 13, wherein the first planarization layerand the second planarization layer include organic insulating materials.19. The display device of claim 13, wherein the common electrode blockis electrically connected to the TSL through another hole in the secondplanarization layer.
 20. The display device of claim 19, wherein thesecond protective film is in contact with a side surface of the otherhole of the upper planarization layer.